Friday, August 27, 2010

System File Checker ( SFC) at Windows

SFC is System File Checker. SFC is running in system to protect system files. All the system files are located in C:\Windows and C:\Windows\System32 folders. These files are important for Windows Operating to work effeciently. If any of the files is deleted accidently the file gets restored from the DLLCache folder automatically with the help of SFC. 


Sometimes, you might need to disable the SFC for development and testing purpose. This article explains the registry keys you can play with to disable the SFC and various options.



  • KEY Name:HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon
  • Entry Name: SFCDisable
  • Date Type: REG_DWORD
  • Value: 0,1,2,3,4
  • 0 = enabled. This is the default option. The SFC is enabled by default on Windows Systems.
  • 1 = disable the SFC. The value 1 disable the SFC but prompt the user at the boot to re-enable the SFC.
  • 2 = This is to disable the SFC completely and users are not prompted to re-enable it.
  • 4 = SFC is enabled but the popups are disabled.



At the same location at registry, you can configure one more registry entry: SFCScan. Data type for this is REG_DWORD and values could be 0,1,2. This entry can be useful to perform the scan of protected files of the systems.



  • 0 = do not scan protected files at boot (default)
  • 1 = scan protected files at every boot
  • 2 = scan protected files once